Towards Autonomous Cars: The Effect of Autonomy Levels on Acceptance and User Experience

Surveys [8] show that people generally have a positive attitude towards autonomous cars. However, these studies neglect that cars have different levels of autonomy and that User Acceptance (UA) and User Experience (UX) with autonomous systems differ with regard to the degree of system autonomy. The National Highway Traffic Safety Administration (NHTSA) defines five degrees of car autonomy which vary in the penetration of cars with Advanced Driver Assistance Systems (ADAS) and the extent to which a car is taken over by autonomous systems. Based on these levels, we conducted an online-questionnaire study (N=336), in which we investigated how UA and UX factors, such as Perceived Ease of Use, Attitude Towards using the system, Perceived Behavioral Control, Behavioral Intention to use a system, Trust and Fun, differ with regard to the degree of autonomy in cars. We show that UA and UX are highest in levels of autonomy that already have been deployed in modern cars. More specifically, perceived control and fun decrease continuously with higher autonomy. Furthermore, our results indicate that pre-experience with ADAS and demographics, such as age and gender, have an influence on UA and UX.